Conventionally, there has been known a technique that sets a constant unit quantity of, for example, a charging time and a charging capacity, and performs charging in order by the unit quantity, when a total quantity of charging capacities of a plurality of charging target vehicles exceeds a chargeable capacity, so as to eliminate uncharged electric vehicles (see JP2011-244630A).
However, the technique in JP2011-244630A sets the order of the vehicles to charge according to the first-come basis, and necessary periods for charging and planned departure times of the respective vehicles are not considered. Therefore, this technique has a problem that there possibly occurs a situation in which even a vehicle whose necessary period for charging is short and planned departure time is approaching has to wait for charging of vehicles that have sufficient time to spare until the planned departure times.